http://bancoderecursoseducativos.weebly.com/matemaacutetica.html
http://www.recursoseb1.com/portal3/index.php/arquivo-de-ficheiros.html?func=select&id=11
http://www.quadroegiz.com/p_17.htm
http://www.quadroegiz.com/p_18.htm
http://www.quadroegiz.com/p_19.htm
http://www.quadroegiz.com/p_20.htm